If you have struggled to lose weight, there is a good chance you have asked yourself this question:

“Is my metabolism just slow?”

Maybe you are over 40. Maybe you are going through menopause. Maybe you have PCOS. Maybe you have spent years losing and regaining the same weight. Maybe you feel like you barely eat, you exercise, and the scale still refuses to move.

Eventually, it becomes easy to believe that something must be wrong with your body.

And maybe there is.

But instead of assuming your metabolism is broken, let’s actually find out.

What Does It Actually Mean to Have a “Slow Metabolism”?

Your metabolism is not one hormone, one organ, or one switch that gets turned on and off.

Your body is constantly using energy just to keep you alive. Your brain needs energy. Your heart needs energy. Your liver and kidneys need energy. Your muscles need energy. Breathing, circulating blood, maintaining body temperature, repairing tissue, and running your nervous system all require calories.

The amount of energy your body uses while at rest is commonly referred to as your resting metabolic rate, or RMR.

Then you burn additional calories digesting food, walking, standing, working, exercising, fidgeting, cleaning the house, and everything else you do throughout the day.

Together, those components make up your total daily energy expenditure, or TDEE.

So when someone says, “I have a slow metabolism,” what we really need to ask is:

Is your body actually using substantially less energy than we would reasonably expect for someone of your age, size, sex, and body composition?

That is a question we can investigate.

Your Body Has an Energy Bill Before You Even Get Out of Bed

Your organs are metabolically expensive.

Research estimates that, per kilogram of tissue, the brain uses roughly 240 calories per day, the liver around 200 calories, the heart and kidneys approximately 440 calories, and skeletal muscle around 13 calories per kilogram per day at rest.[1]

Obviously, your brain does not weigh a kilogram exactly, nor do your heart and kidneys, so these numbers are not meant to calculate your personal metabolism from individual organs.

The point is much simpler:

Your body requires a substantial amount of energy just to remain alive.

You already have a calorie requirement before we add steps, workouts, cardio, work, chores, or digestion. (PubMed)

Let’s Put Real Numbers on This

According to the CDC, the average American woman age 20 and older weighs approximately 171.8 pounds and stands about 63.5 inches tall, just under 5'4".[2] (CDC)

Take a 45-year-old woman around that size.

Using the Mifflin-St Jeor equation, one of the most commonly used equations for estimating resting energy expenditure, her estimated RMR would be approximately:

1,400 calories per day.

That is not her maintenance calorie intake.

That is approximately what her body is predicted to require at rest.[3] (PubMed)

Now consider a 45-year-old woman who is 5'4" and weighs 220 pounds.

Her predicted RMR is approximately:

1,630 calories per day.

Again, that is before normal movement and exercise.

So if a 220-pound woman tells me:

“I have been eating 1,200 calories every single day for months, exercising consistently, and my average weight has not changed at all.”

I am not immediately going to tell her:

“Your metabolism is broken.”

But I am absolutely going to say:

Something here deserves investigation.

Because under normal circumstances, the math does not make much sense.

That does not automatically mean she is lying.

It means we need better data.

Can Someone Actually Have an Abnormally Low Metabolism?

Yes.

There are legitimate medical conditions, medications, and physiological circumstances that can alter energy expenditure, appetite, body composition, fluid balance, or body-weight regulation.

The important distinction is that having difficulty losing weight is not itself a diagnosis of metabolic dysfunction.

Hypothyroidism

Hypothyroidism can reduce energy expenditure and contribute to weight gain.

But the effect is often exaggerated in the weight-loss industry.

The American Thyroid Association reports that approximately 5 to 10 pounds of weight gain may commonly be attributable to hypothyroidism, depending on severity, and much of that additional weight can come from salt and water retention.

Once hypothyroidism is appropriately treated and thyroid hormone levels normalize, the ability to gain or lose weight is generally similar to someone without thyroid disease.[4] (American Thyroid Association)

So hypothyroidism is absolutely real.

“My thyroid is making it physically impossible for me to lose 80 pounds” is a very different claim.

Cushing Syndrome and Other Endocrine Disorders

Cushing syndrome can profoundly affect fat distribution, muscle mass, appetite, glucose metabolism, and body weight.

But Cushing syndrome is uncommon, and obesity alone is not considered sufficient reason to screen everyone for it.

The Endocrine Society recommends testing when there are additional signs that raise clinical suspicion, such as unusual or progressive features associated with cortisol excess.[5] (Endocrine Society)

Other pituitary or hypothalamic disorders can also affect weight regulation.

These are legitimate medical issues.

They belong in a medical evaluation, not a social media diagnosis.

Medications Can Matter Too

Certain medications can meaningfully influence body weight.

Examples include some antipsychotics, antidepressants, glucocorticoids, insulin, certain anticonvulsants, and other medications.[6] (PubMed)

Sometimes the mechanism is increased appetite. Sometimes it involves glucose regulation, fluid retention, sedation, decreased activity, or several mechanisms at once.

Again, that does not mean energy balance disappeared.

It means one or more variables affecting energy balance changed.

If your weight changed dramatically after starting or changing a medication, talk to the medical professional prescribing it. Do not stop a prescribed medication on your own.

Now Let’s Talk About What Does NOT Automatically Mean You Have a Slow Metabolism

This is where I think a lot of unnecessary fear gets created.

Certain life stages and medical conditions can make weight management more challenging.

That is not the same thing as saying your metabolism is broken.

“I’m Over 40, So My Metabolism Has Slowed Down”

This one gets repeated constantly.

But one of the largest studies ever conducted on human energy expenditure found that, after accounting for body size and composition, adjusted energy expenditure remained surprisingly stable throughout adulthood from approximately age 20 through age 60.[7] (PubMed)

That does not mean nothing changes between 20 and 60.

A lot can change.

You may lose muscle.

You may become more sedentary.

Your job may require more sitting.

You may sleep less.

You may exercise less.

You may have children, work responsibilities, injuries, stress, or lifestyle changes.

Those things can absolutely change how many calories you burn and consume.

But your metabolism does not suddenly fall off a cliff because you turned 40.

“I’m in Menopause, So My Metabolism Is Broken”

Menopause deserves more nuance.

The menopause transition can affect body composition, fat distribution, muscle mass, sleep, physical activity, and metabolic health.

Research has also reported decreases in energy expenditure during the menopause transition in some populations, although newer reviews emphasize that separating the independent effects of menopause from aging, loss of lean mass, and lifestyle changes remains complicated.[8] (PubMed)

So I am not going to tell a woman:

“Menopause changes nothing.”

That would be ridiculous.

But I am also not going to tell her:

“Estrogen dropped, therefore your body can no longer lose fat.”

Menopause may change some of the variables.

It does not eliminate the process.

“I Have PCOS, So My Metabolism Barely Burns Calories”

PCOS is another area where the internet tends to take a complicated condition and reduce it to:

“Your metabolism is broken.”

The research is much more nuanced.

A 2024 study comparing 266 women with PCOS with 51 controls found similar absolute resting energy expenditure between groups, although energy expenditure relative to fat-free mass was lower in the PCOS group.[9] Other studies have produced conflicting findings. (PubMed)

So PCOS may affect several factors related to weight management, including insulin sensitivity, appetite regulation, reproductive hormones, and possibly energy expenditure in some women.

But PCOS does not automatically mean your body suddenly requires extraordinarily few calories.

Having PCOS and struggling with weight loss is not proof that your metabolism is broken.

What About Years of Dieting? Can You Damage Your Metabolism?

Your body can absolutely adapt to weight loss.

When you lose weight, you become a smaller person.

A smaller body generally requires less energy.

You may also lose some lean mass.

You are eating less food, so the thermic effect of food decreases.

Your spontaneous movement may decline.

And adaptive thermogenesis can occur, meaning your energy expenditure may fall somewhat more than would be predicted solely from your change in body size and composition.

That phenomenon is real.

But adaptation is not the same thing as damage.

A systematic review of 33 studies involving 2,528 adults found evidence of adaptive thermogenesis in many studies. However, the effect tended to be smaller in higher-quality research and could become attenuated after periods of weight stabilization or neutral energy balance.[10] (PubMed)

Your metabolism can adapt.

That does not mean you destroyed it.

And it certainly does not automatically mean the solution is to enter a calorie surplus and start gaining weight to “repair your metabolism.”

Then Why Do So Many People Believe They Barely Eat?

Because accurately tracking food is much harder than most people realize.

And this is not an insult.

Researchers have demonstrated it repeatedly.

A systematic review examined 59 studies containing 6,298 free-living adults in which self-reported calorie intake was compared with energy expenditure measured using doubly labeled water.

The majority of studies found significant underreporting of calorie intake.[11] (PubMed)

Other research has found particularly large discrepancies in some obese populations.[12] (PubMed)

That does not mean everyone intentionally lies about their food.

Most people probably don't.

It means humans are simply not very good at remembering and estimating everything they consume.

Calories Are Extremely Easy to Miss

Think about how easy this can happen.

A little extra cooking oil.

Coffee creamer.

A handful of nuts.

A restaurant meal.

Alcohol.

Condiments.

A few bites while cooking.

A larger portion than you estimated.

Friday night.

Saturday afternoon.

Sunday dinner.

None of those individual decisions has to feel excessive.

But together, they can completely change your weekly calorie intake.

We live in a food environment where calories are cheap, convenient, concentrated, highly palatable, and incredibly easy to consume.

You can consume 1,000 calories very quickly without feeling like you just ate an enormous amount of food.

That is one reason why “I don't eat that much” and “I don't consume many calories” are not necessarily the same statement.

The Same Problem Happens With Movement

Ask someone:

“Are you active?”

She may immediately answer:

“Yes. I work out three times per week.”

Then you look at her step average.

3,200 steps per day.

Exercise and daily movement are not the same thing.

You can complete a hard 45-minute workout and still spend the overwhelming majority of your waking hours sitting.

That is why I do not want to guess.

I want to know.

How many calories are you actually averaging?

How much protein are you actually eating?

How many steps are you actually taking?

How often are you actually training?

How much cardio are you actually doing?

What is your average body weight actually doing?

Not what you planned to do.

Not what you think you usually do.

What are you consistently doing?

What I Have Seen Coaching Hundreds of Women

I have coached hundreds of women who genuinely believed they had slow metabolisms.

Some believed they barely ate.

Some believed turning 40 changed everything.

Some blamed menopause.

Some had PCOS.

Some had spent decades dieting.

And over the last few years, I have even coached women who believed they were “nonresponders” to GLP-1 medications because they were not losing the amount of weight they expected.

Once we actually started collecting data, we often discovered something much less mysterious.

Their calorie intake was higher than they realized.

Their movement was significantly lower than they thought.

Their eating was inconsistent.

Their weekends looked completely different from their weekdays.

Or it was some combination of all of those things.

That does not mean this is what is happening to you.

I have zero data on you.

And that is exactly the point.

Neither you nor I should diagnose your metabolism based on a belief.

Don’t Believe It. Investigate It.

This is my philosophy with almost everything involving weight loss:

Do not waste months or years believing something that may not even be true. Find out.

If you genuinely believe something is medically wrong with your body, talk to your primary care provider.

Explain what you are experiencing.

Discuss your symptoms.

Review your medications.

Get appropriate testing.

Clinical endocrine guidelines recommend evaluating thyroid function in obese adults, while more specialized hormonal testing should generally be based on symptoms and clinical suspicion rather than assuming every weight-loss plateau is an endocrine disorder.[13] (OUP Academic)

And while your doctor investigates the medical side, investigate the behavioral side too.

Start collecting your own data.

Know your calories.

Know your protein.

Know your steps.

Know your training frequency.

Know your cardio.

Know what your body weight is actually doing over time.

Because if you cannot answer those questions, you do not yet have enough information to conclude that your metabolism is the problem.

Find Your Baseline

The goal is to reach a point where you understand what I call your baseline.

Your baseline answers a simple question:

“What am I consistently doing right now that is producing my current result?”

Once we know that, everything gets easier to troubleshoot.

If your body weight is relatively stable while your calories, movement, and training are relatively consistent, now we have a starting point.

Then we can make an adjustment.

Maybe calories decrease.

Maybe movement increases.

Maybe cardio increases.

Maybe we use a combination.

Maybe consistency itself is the biggest thing that needs to improve.

Or maybe your doctor identifies a legitimate medical problem that needs treatment.

Whatever the answer is, we now have something much more useful than speculation.

We have information.

We have a baseline.

And now we can work on the actual solution.

Don't Guess About Your Metabolism

You may have a medical condition affecting your weight.

You may have experienced some metabolic adaptation.

You may be more sedentary than you realize.

You may be consuming more calories than you realize.

It may be several things happening at once.

I cannot tell you which one applies to you without knowing anything about you.

But I can tell you this:

Believing your metabolism is broken without investigating it does absolutely nothing to solve the problem.

Find the truth.

Establish your baseline.

Identify what actually needs to change.

Then make the adjustment and move forward.

Do not spend another year fighting a problem you have never confirmed exists.

Ready to get Results?

Inside Get Lifted University, I teach you how to identify your baseline, understand your calories, movement, nutrition, and training, and make adjustments based on what your body is actually doing.

If you want to learn the system and have the education and guidance to implement it yourself, join Get Lifted University.

If you want my team and me to personally evaluate your situation, establish your starting point, and guide you through the process, apply for 1-on-1 coaching.

Don't guess about your metabolism. Let’s find out what is actually happening.

God bless. Let’s work.

References

1. Wang Z, Ying Z, Bosy-Westphal A, et al. Specific metabolic rates of major organs and tissues across adulthood: evaluation by mechanistic model of resting energy expenditure. American Journal of Clinical Nutrition. 2010;92(6):1369-1377. doi:10.3945/ajcn.2010.29885. (PubMed)

2. National Center for Health Statistics, CDC. Body Measurements: Measured average height, weight, and waist circumference for U.S. adults ages 20 and older. Data source: August 2021-August 2023. (CDC)

3. Mifflin MD, St Jeor ST, Hill LA, Scott BJ, Daugherty SA, Koh YO. A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition. 1990;51(2):241-247. doi:10.1093/ajcn/51.2.241. (PubMed)

4. American Thyroid Association. Thyroid and Weight. The ATA reports that roughly 5 to 10 pounds of weight gain may commonly be attributable to hypothyroidism, much of it related to salt and water retention. (American Thyroid Association)

5. Nieman LK, Biller BMK, Findling JW, et al. The Diagnosis of Cushing's Syndrome: An Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology & Metabolism. 2008;93(5):1526-1540. (Endocrine Society)

6. Pharmacotherapy causing weight gain and metabolic alteration in those with obesity and obesity-related conditions: A review. 2024. Review of medication classes associated with weight gain, including glucocorticoids, antipsychotics, antidepressants, insulin, and others. (PubMed)

7. Pontzer H, Yamada Y, Sagayama H, et al. Daily energy expenditure through the human life course. Science. 2021;373(6556):808-812. doi:10.1126/science.abe5017. (PubMed)

8. Juppi HK, Karppinen JE, Laakkonen EK. Menopause and Body Composition: A Complex Field. 2025. The review discusses changes in skeletal muscle, adipose tissue, and metabolic health while emphasizing uncertainty regarding the independent effect of menopause on resting energy expenditure. (PubMed)

9. Tosi F, Rosmini F, Gremes V, et al. Resting energy expenditure in women with polycystic ovary syndrome. Human Reproduction. 2024;39(8):1794-1803. doi:10.1093/humrep/deae129. (PubMed)

10. Nunes CL, Casanova N, Francisco R, et al. Does adaptive thermogenesis occur after weight loss in adults? A systematic review. British Journal of Nutrition. 2022. Thirty-three studies involving 2,528 participants were included. (PubMed)

11. Burrows TL, Ho YY, Rollo ME, Collins CE. Validity of Dietary Assessment Methods When Compared to the Method of Doubly Labeled Water: A Systematic Review in Adults. Frontiers in Endocrinology. 2019;10:850. doi:10.3389/fendo.2019.00850. (PubMed)

12. Black AE, Prentice AM, Goldberg GR, et al. Inaccuracies in self-reported intake identified by comparison with the doubly labelled water method. Research reviewed substantial individual discrepancies between reported intake and measured expenditure, including particularly large discrepancies in obese populations. (PubMed)

13. Pasquali R, Casanueva F, Haluzik M, et al. European Society of Endocrinology Clinical Practice Guideline: Endocrine work-up in obesity. European Journal of Endocrinology. 2020;182(1):G1-G32. doi:10.1530/EJE-19-0893. (OUP Academic)